Work with strings with stringr : : CHEAT SHEET

Work with strings with stringr : : CHEAT SHEET

The stringr package provides a set of internally consistent tools for working with character strings, i.e. sequences of characters surrounded by quotation marks.

Detect Matches

Subset Strings

Manage Lengths

TRUE

str_detect(string, pattern) Detect the

TRUE

presence of a pattern match in a string.

FALSE TRUE

str_detect(fruit, "a")

1

str_which(string, pattern) Find the indexes of

2

strings that contain a pattern match.

4

str_which(fruit, "a")

str_sub(string, start = 1L, end = -1L) Extract substrings from a character vector. str_sub(fruit, 1, 3); str_sub(fruit, -2)

str_subset(string, pattern) Return only the strings that contain a pattern match. str_subset(fruit, "b")

4

str_length(string) The width of strings (i.e.

6

number of code points, which generally equals

2 3

the number of characters). str_length(fruit)

str_pad(string, width, side = c("left", "right", "both"), pad = " ") Pad strings to constant width. str_pad(fruit, 17)

0

str_count(string, pattern) Count the number

3

of matches in a string.

1 2

str_count(fruit, "a")

start end

str_locate(string, pattern) Locate the

24 47

positions of pattern matches in a string. Also

NA NA

str_locate_all. str_locate(fruit, "a")

34

str_extract(string, pattern) Return the first

NA

pattern match found in each string, as a vector.

Also str_extract_all to return every pattern

match. str_extract(fruit, "[aeiou]")

str_match(string, pattern) Return the first

pattern match found in each string, as a

NA NA

matrix with a column for each ( ) group in

pattern. Also str_match_all.

str_match(sentences, "(a|the) ([^ ]+)")

str_trunc(string, width, side = c("right", "left", "center"), ellipsis = "...") Truncate the width of strings, replacing content with ellipsis. str_trunc(fruit, 3)

str_trim(string, side = c("both", "left", "right")) Trim whitespace from the start and/or end of a string. str_trim(fruit)

Mutate Strings

Join and Split

Order Strings

A STRING a string

a string A STRING

a string A String

str_sub() ................
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